Motor-controlling device.



T. w. NOWELL. MOTOR CONTROLLING DEVICE. APPLICATION FILED MAY 19, 1911.

Patented Oct. 22, 1912.

2 SHEETSSHBET 1 /17 we, to r" Thomas W/Vowe/A QZW /-//s AttorneyW/tnesses:

' T. W. NOWBLL.

MOTOR CONTROLLING DEVICE.

APPLIQATION IILEDYMAY 19, 1911.

1,041,859. Patented Oct.22,1912.

2 SHEETSSHEET 2 v l V/tnesses: /27 van to)" 1 Thomas W/Vowe/L q (I 6 W14His Attorney UNITED STATES PATENT OFFICE.

THOMAS W. NOWELL, OF SOHENECTADY, NEW YORK, ASSIGNOII. TO GENERALELECTRIC COMPANY, A CORPORATION OF NEW YORK.

MOTOR-CONTROLLING DEVICE.

To all whom it may concern: Be it known that I, THOMAS \V. NowELL,

a citizen of the United States, residing at Schenectady, county ofSchenectady, State of New York, have invented certain new and usefulImprovements in Motor-Controlling of this character in which the speedat which the controlling operation is performed is positively limited ina simple and reliable manner.

One of the objects of my invention is to provide a controlling devicewith simple and positive means whereby the movement of the controllingmember is automatically stopped for an instant at a predetermined pointand may then be continued by the operator.

While my invention is applicable to vari- "ous types of controllingdevices, it is particularly well adapted for motor controllin devices ofa character in which the cone tro lin arm is moved from the initial orofi position through the starting position to running position. y ment.In the starting of motors with starting devices of this character,especially where the starting is performed in a single step, it isdesirable that there be some means for preventing the operator frompassing.

too quickly through the starting position so as to establish runningconnections before the motor has come up to speed.

In carr'yin means where y when the operator reaches the startingposition, the controlling. arm is positively stopped and in order thatthe startingarm may be continued to running position it is necessary togive the controlling arm a'sli'ght movement in a backward direction.

Other objects and purposes of my inven tion will appear in the course ofthe following specification in which I have shown my invention'em'bodiedin concrete form for purposes of illustration.

Referring to the drawings illustratingone form of my invention, Figure lis a plan view of my device, showing the circuit connections; '2 is aside elevation of the same; Fig 3 is a view showing the Speci fi eItionof Letters Patent.

Application filed May 19, 1911. Serial No. 628,163.

a unidirectional move- 3 out my invention I provide Patented Oct.22,1912.

controlling arm in the starting position;

and Fig. 4 shows the starting arm after it has been reversed farg oughto permit the movement of the arm to retirin position.

Referring to the drawing, it will be-seen that I have shown my inventionin connection with the starting of a single phase motor by means of whatis known as a split phase connection, but it is obvious that myinvention is in no sense limited to the particular form of motor orconnections for starting the same. fore, 10 represents an insulatingbase of slate or soapstone having mounted thereon the controlling arm 11pivoted at 12 and biased or spring pressed to the off position againstthe stop 13 by means of the spring 14. 'The contact on the controllingarm in the off position is in contact with the insu- In the drawing,there,

ing segment 18. In order to hold the con-,

trolling arm in running position I provide a spring pressed latch 19pivoted at 20 and spring pressed so that the notch 21 in the end of thelever will engage with a pin 22 on the controlling arm when the latteris in running position. The opposite end of the lever projects outwardso as to be engaged by the plunger 23 of the no-voltage magnet when itdrops and thereby release the controlling arm and allow it to return tothe off position. In this type of starting device it is desirable toprevent the operator from passing through the's'tarting position tooquickly. In other words, it is desirable that the operator be requiredto stop for an 'instant in the starting position so as to give the motora short interval of time in which to speed up. .One of the principalfeatures of my invention, therefore, is the provision of means foraccomplishing this result. To this end I provide in connectionwith thecontrolling arm a detent member 24: which isadapted to engage the stop25 when the arm is moved to starting position. This detent is secured tothe controlling arm by means of the pin 26 secured to the arm. This pinpasses through a slot 27 in the detent so as to act as a pivot for thedetent. The ,pin moves easily in-the slot 27 from one yieldingly intocontact with the care. The

point 32 at which the springf O is secured to the detent is in such aposition that it is on opposite sides of the pivot 26 when the latter isat opposite ends of the slot.

As shown in Fig. 1, the pivot 32 is to the right of the pivot pin, whilein the position shown in Fig. 3 the pivotal point 32 is to the left ofthe pivot pin. In other words, the point 32 is between the lines drawnfrom the point 31 to the two positions occupied by the pivot pin atopposite ends of the slot. In the position shown in Fig. 1, therefore,the finger of the detent is held against the cam face of the stop whilein the position shown in Fig. 3 the spring tends to move the detentfinger away from the cam face out the stop. It will be observed,however, that when the finger is against the stop thepoint'of the fingeris in the recess 29 so that the finger can not leave the face of thecalm until the arm backed the finger out of the recess.

The mode of operation of my device is as follows: with the parts in theposition shown in Fig. 1, the controlling arm lever is spring pressed tothe ofi position and the detent 2% is pressed against the stop or bufferllift-orcing the detent into the position shown in Fig. 1. In thisposition. the spring 30 is pulling the detent into engagement with thecam face'of'the stop 25. As the arm is moved to the right to start themotor the contact arm engages the contact 33 which energizes the novoltage magnet so as to move the plunger 23 out of engagement with theLIIH of the latch 19. When the arm is mov ed to the position shown inFig. 3, the starting connections 'are made. These connections are shown,for purposes of illustration, as being of the split phase type in whichthe resistance 34 and the reactance 35 are connected in parallel acrossone of the windings 0'? the motor .These connections gire to the motor astarting torque. It is Iecessary, however, that the arm be held in thisposition at least for an instant in order that themotor may be started.In this position it will be observed that the finger 28 of the detententers the recess 29 of the stop and positively prevents any furthermovement. As the arm moves toward the starting. position the detent' isin the position shown in Fig. 1. "When, however, the starting fingerengages the stop, the pivot pin :36 moves forward in the slot 2? untilit reaches the position shown in witness Fig. 3. As the pin 32 passes tothe opposite side of the pivot, the tension on the detent is reversed sothat with the parts in the position shown in 3, the bias or tendency ofthe spring is to move the finger away "from the cam face of the stop.This movenient,however, is restrained by the fact that the finger 18 inthe recess 29. 'lhe operator therefore reaches the starting position inwhich the resistance and reactance windings are in circuit and steps. Inorder to get' farther, e he moves the handle back a short distancesufiicient to take the 28. out of the recess 29. As soon as this is?done the spring throws the finger into the position shown in Fig. 4. Theoperator is F now able to continue the movement to run- 1 ning position,in which the arm. is held by the latch 19. On failure of voltage theplunger 23 of the no-voltage magnet will be released and trip the latch19, thereby returning the arm to the 05 position. As the" arm strikesthe buiier 13 the detent is again shifted on its pivot to the positionshown in. Fig. 1. The net resultis that the operator can not possiblypass through the starting position without stopping and reversingslightly, which movement will take a small amount of time suthcient toenable the motor to get started.

While I have described my invention in connection with the controllingof a par ticular type of motor and as operating in a specific manneraccordance with the patent statutes, it should be understood that Ivarious modifications thereof will suggest themselves to those skilledin the art without departing from the spirit of my invention, the scopeof which is set forth in the annexed claims.

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is,-- 1. A controlling device for electric circuits comprising acontrohing arm, a co operating stop and dct-ent mechanism associatedwith said arm biased to lock the arm when the latter is moved to apredetermined position and means whereby the detent is biased away fromthe stop by the pressure of the detent against the stop and is releasedtherefrom by a backward movement. 2-.' A controlling device for electricpircuits comprising a controlling arm, a' j detent mounted thereon andbiased to locin ng position, a recessed stop arranged to receive saiddetent at a predetermined point in'its travel when the detent isinloclning position, and means whereby the bias on said detent isreversed by the pressure of thedetent in the recess so as to cause thedetent to nioveput of the path of the stop when released from therecess.

3. A. controlling device for electric circuits comprising a controllingarm, a reat .do not limit my invention thereto, sincecesseol stop, adetent on said arm having a locking position in which it enters therecess at a predetermined point of its travel and a releasing positionin which it is out of the path of the stop, and means whereb the -detentis held in looking position whi e the arm is being moved to saidpredetermined point and is biased toward releasing position byengagement with the stop so that the detent will move to releasingpositionwhen moved out of the recess.

4. A controlling device for electric cir cuits comprising a controllingarm, a recessed stop, a detent mounted on the arm and biasedto enter therecess at a predetermined point in the travel of the arm to stop thesame, and means whereby the bias on the detent is reversed by thepressure of the detent against the stop so that the de- 90 tent willmove out of the path of the stop when released from the recess.

5. A controlling devicefor electric circuits comprising a controllingarm, a pivot pin on said arm, a detent movable on said pivot to changethe pivotal point thereof, a

spring having one end secured to the armand theopposite end secured tothe detent at a oint between the pivotal points so that t is spring willact upon opposite sides of the pivot in opposite pivotal positions ofthe detent, and a stop for engaging the detent in a predeterminedposition of said arm.

6. A controlling device for, electric circuits comprising a controllingarm, a pivot pin mounted on said arm, a detent movable on said pivot tochange the pivotal point thereof, a spring having one end secured to thearm and the opposite end secured to the detent at a point between linesdrawn from the securing point on the arm to the opposite pivotal points,a stop for engaging the detent at a predetermined point in the travel ofsaid arm to hold it while the pivot is moved to its opposite pivotalpoint, and a stop at the initial position of the arm for en-- gaging thedetent and moving it to the other pivotal point. i

In witness whereof, I have hereunto set my hand this 17th day of May,1911.

THOMAS WV. NOWVELL.

Witnesses:

HELEN ORFORD, BENJAMIN B. HU L.

copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Wilmington, D. C.

